At the present time various types of gas generators have been developed and are used in industry, which use external (electrical) energy as well as energy from th e environment, i.e. so-called surface gasifiers. One example of such a gasifier is the low-pressure gasifier GH-0,035/1,6 (SU 7 186 692) consisting of two cylindrical high-pressure tanks for storing cryogenic liquids under a pressure of up to 1,6 MPa and transporting them, and a production vaporizer for gasification. The production vaporizer consists of a block of panels arranged in a frame. The liquid product is discharged from the tank under pressure, is fed into the panels of the vaporizer and gasifies by heat exchange with the environment without additional use of energy. There is a whole range of low pressure cryogenic gas generators in use that work in analogy to this principle. However, they all have essential disadvantages, that is, their low productivity of the gaseous product in conditions of mass production. Thus, the maximum productivity of a GHK 25/1,6-2000 apparatus is 2200 cubic meters per hour (0,6 cubic meters per second) at an occupied space of 86,6 square meters and a mass of 19,2 tons.
More effective is a gas generator for use in fire extinguishing plants according to SU 1 678 391, which comprises an isothermal vessel, an electrically controlled valve, and a supercharging evaporator. The isothermal vessel in this gas generator is connected via an electrically controlled valve to the lower part of the evaporator of the gasifier and to a mixing chamber, in which turbulence-creating grids and filling inlets are arranged. However, the essential disadvantages of this gas generator are the following: Firstly, in this gas generator construction the quantity of gas generated cryogenic liquid is determined by the mass of the heat-accumulating inlet. Therefore an increase in the productivity of the apparatus is dependent on an increase in the mass of the heat-accumulating inlet, which, as a rule, is made of a metal with a great heat capacity or of natural materials, such as gravel, crushed stone etc. Secondly, additional time and the supply of external energy are needed to prepare the apparatus for the second working cycle, i.e. to reheat it.